Two Souls, One Story
by D3athd0uspart
Summary: What if Frisk had help while being in the under ground? What if they lived together? What if they fell in love with monsters?
1. Chapter 1

**Hey. This is my first fanfic… please enjoy.**

Frisk woke up onto a bed of golden flowers, the feeling of being watched consumed her. She turned, looking for anything out of the ordinary. _Nothing. Just your imagination. Like always…_

"H-hello?" the voice shocked Frisk, and caused her to spin around, seeing a girl a little bit older than her, with light brown hair that had an entire section dyed red and blue. She wore a black tank top with a skull on it, and jean shorts. She had black combat boots, and a bracelet with a charm for the treble clef on it. Ivy green eyes looked at her, filled with shock and concern.

"A-are you hurt? Did the fall break a bone?" the girl quickly rushed over, reminding Frisk of an over-bearing sister. "C'mon, we should try to get out of here. What's your name?" The girl took Frisks hand and led the small child to a doorway.

"Frisk…" Frisk had mumbled, only loud enough for the older girl to hear. "Ok. Well, I'm Katherine. Nice to meet you." Katherine smiled at the tiny girl, and they soon found a small clearing the had a golden flower sitting in it. The duo walked up to the plant, only to be surprised when it could speak.

"Howdy! I'm Flowey. Flowey the Flower. You two are new to the underground, aren'tcha? Golly, you two must be so confused. Someone ought to teach you how things work around here! I guess little old me will have to do. Ready? Here we go!" The two girls exchanged looks, and both saw a red heart floating in front of them. "See that heart? That is your SOUL, the very culmination of your being! Your SOUL starts out weak, but can grow strong if you gain a lot of LV. What's LV stand for? Why, LOVE, of course! You want some LOVE, don't you? Don't worry, I'll share some with you!" A strange expression crossed on Katherine's face, and she squeezed Frisk's hand. "Down here, LOVE is shared through little white 'Friendliness pellets'. Are you ready? Move around! Get as many as you can!" Frisk watched as all the pellets came at their souls, leaving the red things quivering. Katherine glanced at the heart and then the flower. The flower said some things, then the girls met Toriel.

(Ten-year time skip, Frisk and Katherine have freed everyone from the underground…)

Frisk stared at the TV, which had an anime that Katherine was forcing Alphys and Undyne to watch. Undyne was ranting about no violence in the anime, and how it was boring. Alphys however… was enjoying it a little too much; She fangirled the entire time. Frisk got up and entered the kitchen of the house she and Katherine had shared for the past five years. Papyrus was calmly talking to Asriel, **(A/N: Yes, Asriel is alive. Yes, I made him alive on purpose.)** whom was the same age as Frisk, and who Frisk had a tiny (huge) crush on. Frisk looked over to her right and saw Mettaton glaring at Sans, who was glaring back. Frisk let out a sigh and walked to the fridge and tapped Papyrus to move, who was blocking the way to get to the door.

"OH, HELLO YOUNGER HUMAN, WE HAVE NOT SPOKEN YET, HOW HAVE THINGS BEEN?" Papyrus asked Frisk, who calmly replied with a smile and two thumbs up. "HOW IS YOUR SISTER?" Frisk's smile didn't falter; she knew he was talking about Katherine. They decided together that they'd say that they were sisters; Katherine being older and Frisk being younger. In response to Papyrus's question, she gave him a thumbs up and waved to Asriel, before grabbing her water and walking back into the living room blushing.

Frisk POV.

Why did Katherine invite him?! I knew he was staring at me the moment I started talking to Papyrus… WHY WAS I BEING RUDE?! I walked past my 'sister' and saw her doodling something in her sketchbook while Undyne and Alphys watched the anime's finale. I looked over the couch and saw her sketch in the beginning process. I could see her figure in the background, but I couldn't see what she was currently drawing in the picture. I walked back into my seat and just then the anime ended, and Alphys freaked out about the ending being so good, and Undyne just shrugged.

The guys walked out of the kitchen, and I watched as Sans walked over to Katherine and asked her something. She jumped and quickly shut her sketchbook, and nodded and got up.

"Well, bye dorks!" Undyne yelled, carrying Alphys and running home.

"UNDYNE! WAIT FOR ME!" Papyrus yelled, and ran after the fish woman and yellow dinosaur. I should note that they got out, and the door froze behind them… Asriel had turned the doorknob and pulled, the door refusing to budge.

"Well, shit. Mom's going throw a fit. I'm going to call her." He mumbled and pulled out his phone and called Toriel. He walked into a corner and told the goat woman his situation.

"You guys can just stay here for the night, it's no issue, really. One of you can sleep in my room and the other can sleep in the guest room." I suggested, and Sans shrugged and nodded, and Asriel told his mother my offer, and looked at me and signaled a thumbs up. I glanced at Katherine who had already gone into her room to change. Sans had taken the guest room, so Asriel took my room.

Katherine's POV

It's midnight. I had snuck downstairs to grab my sketchbook, slightly shaky due to the fact a certain short skeleton was in my house, sleeping. I sat in my chair that looks outside and started continuing my drawing. I paused and looked outside, and saw the snow falling at an increasing pace. Man, I get that Frisk liked this area, between Snowdin and the way to the ruins, but she had to choose the coldest area. Technically, we live in the woods, but just a few miles out of Snowdin.

"heh. guess we're _snowdin_ , huh?" that familiar voice whispered close to my ear- a little too close. I snapped my book shut, and blushed. I steered my gaze to Sans, to find the usual smirk. I rolled my eyes, and got up.

"I'm guessing you can't sleep either, or you're just hungry." I stated, fully knowing it had to be one of those two. He nodded, signaling it was pretty much both.

"both. i'm guessing you aren't _bone-tired_ , unlike your sis." I snorted at that one.

"Isn't it too late to be cracking jokes?" I asked, while walking into the kitchen to grab something to eat.

"i don't care, as long as i have an audience." He replied nonchalantly. He honestly doesn't realize how much my heart is racing right now….

"What do you want to eat?" I asked, expecting to hear him say something, but I only heard a mumble, sounded like he said he wanted to go to Grillby's. "It's almost twelve-thirty, dude are you joking? We can't go to Grillby's." I said, hoping he'd fess up what he actually said. I looked at him over my shoulder and he looked shocked, and had blue around his cheeks… wait is he blushing?

"Dude? You ok? You look like you're blushing… did you really forget it's," I looked at the clock, "Twelve-Thirty?" he looked at me seriously, and said this,

"i'm tired to the _bone_." That one got me, I started cracking up, and that gave him the opportunity to hit me with pun after pun. "what? can't _mandible_ my jokes?" I continued laughing, and he hit me with another, "I mean, i know my jokes are pretty _hip_ , but i didn't know you found them this _humerus_." Oh god, help me.

"Would you two just smooch already?" A robotic voice from the living room called. Oh shit, I forgot Mettaton was here… I glanced at Sans, who had blue covering his cheekbones. He looked back at me and I blushed redder than a tomato. I grabbed my sketchbook and quickly ran into my room, just by myself- wait, Frisk is there… FUCKING HELL! I still went into my room anyway.

Next Morning, Frisk POV.

I woke up to a frantic Katherine. She was sketching, and kept messing up.

"You ok, sis?" since we called each other sisters for ten years, we've gotten attached to calling each other 'sis'. She looked at me, and from what I could tell, she was probably up all night.

"Ummm, I have no fucking clue." She murmured, and got up to shower. I went downstairs, and saw Asriel, Sans, and… Mettaton? Mettaton was currently telling Sans how he should've kissed 'her' if he liked her. Asriel was the only one facing my direction, and looked at me and shrugged. Mettaton saw the action and looked at me with a worried expression, then relaxed when he saw me.

"Oh, hi darling. We were just talking about something in the past before we met." Mettaton said, looking around nervously. That little…

"Hey guys. Should we try to get out of the house, literally?" I asked, and gave Mettaton a glare he knew well, from Katherine and me. He shivered, and nodded, as did Sans and Asriel. I went upstairs and pulled on my favorite sweater. I then went downstairs and looked out the window where you could see the front of the door. Damn. That's a lot of snow.

Katherine came downstairs in a black hoodie, and dark blue jeans. Also wearing combat boots.

"How bad is it?" an all too familiar voice said behind me. I turned and saw Asriel standing in the doorway.

"We could climb out of the window…" I suggested, and pried the window open, and proceeded to climb outside. And fell into a pile of snow. I climbed out and gave him a thumbs up. I looked to my left and saw that Sans had teleported himself and Katherine out. Aww I ship it. Asriel helped me out of the snow, and I brushed the snow off my sweater.

"Who wants to go to Grillby's?" I heard Katherine call, and Asriel and I gave a thumbs up.

 **Sooooo the group is going to Grillby's… as you can see, I did SansxOC and FriskxAsriel. There will be Papyton too. My friend requested this fic, so I'm doing it. The OC is hers, soooo yea.**

 **Next chapter hint.: Grillby's, Food, Sticky Situations, and… Scary Sisters.**


	2. Chapter 2

**AAAAAANNNNDDD WELCOME BAAAAAAAACK! To be completely honest, I don't think you guys would care if I updated or not….**

Sans POV

I followed everyone to Grillby's, and man, was I tempted to just teleport us there, but no, Frisk said we had to walk.

We FINALLY got to Grillby's to find that it was closed, due to the snow.

"fuck." I mumbled, only Katherine hearing me.

"We could go to the Ruins, the door never freezes…" Asriel offered, and Frisk eagerly nodded. She has it bad for him, damn.

"I'm ok with seeing Toriel. As long as we get out of this cold." Katherine mumbled, then shivered.

"can i just tele-." "NO!" Frisk practically yelled, interrupting my sentence. Katherine glared at her sister, then looked at me.

"SANS TELEPORT!" She yelled, and so I did. We ended up in front of the door to the Ruins. Frisk was going to be pissed when she realizes we teleported without her and Asriel. I looked at Katherine who was texting the younger human. 'Have fun with Asriel' is what she sent. I went up to the door and knocked.

"knock, knock." I waited a moment, then the normal answer came.

"Who's there?" Tori's voice answered from behind the door. "orange."

"Orange who?" her voice sounded slightly confused. "orange you gonna let me in?" I answered, as politely as I could. The door opened, and she looked surprised to see Katherine with me. Katherine waved, and Tori waved back.

"Please, come in." Tori walked inside, and we followed.

We sat down at the table as Tori brought some pie into the room and placed it onto the table.

"So where's Asriel and Frisk?"

Asriel POV

"HOW COULD HE TELEPORT! JUST BECAUSE MY SISTER SAID FOR HIM TO TELE- Holy fucking shit… does he like her?" Frisk yelled/mumbled to herself. I looked at her plainly. "Yeah, he does. Mettaton told me what happened last night; apparently Katherine was sketching and Sans scared the shit out of her, then she offered him food, he said something and she said something then Sans made her laugh- a lot, which was enough to wake up Mettaton… who suggested that they kiss and I didn't hear the rest of the story. But anyways, does she like him?" I let the information sink into Frisk's head, said person getting a grin on her face.

"She likes him, a lot." Frisk jumped suddenly, her phone making a sound, notifying her that she just received a text. Frisk looked at the screen, before flaming up into a deep shade of red.

"That BITCH!" I raised an eyebrow, and leaned against the wall. "Well, should we get going? I want to catch up to them right away." Frisk had a look on her face I wasn't comfortable with. But I brushed it off quickly when she told me her plans, that involved glue and syrup.

We quickly got to Mom's before they could leave. Frisk had put the contents in her dimensional box A, so they wouldn't be seen easily. We walked in, to see Mom and Sans chatting in the living room, Katherine, however was out and about in the Ruins. Sans didn't hesitate to offer to get her, and then he rushed out to get her. Frisk and I shared a sly smile before we told Mom our plans. Let's just say Mom was really on board with this.

Katherine POV

I looked up, the gaping hole looming above me, the blue sky of the surface taunting me, just like it did when I fell down here. When I met Frisk, when my life truly began. I sat on the golden flowers, sighing at the peace I was currently feeling. My phone buzzed, and I got a text, from Sans; 'hey, you awake?'. I quickly spun around, which had nothing there. I turned back around to be face to skull with Sans. I instantly blushed, and backed up. His right eye was glowing blue… that piece of shit.

"Asshole! You scared me!" He just smirked. Damn him.

"wasn't that the point?" I just glared in response. He helped me out of the flowers, and teleported us to the house, which got me really dizzy.

We walked in, and took a seat at the table. I immediately regretted that. I was stuck to the chair, and judging from how Sans was struggling to get up, he was too. Frisk was also sitting down, along with Asriel. They were taking pictures… WHAT THE FUCK?!

Frisk tried getting up, but she couldn't… HAHA YOU FELL FOR YOUR OWN PRANK! I sneered at my little sister, who was blushing- which could rival a tomato.

I moved my gaze to Asriel, whose face was a light pink.

"Wow. You guys actually fell for your own prank." I slowly clapped, a joke well known between my sister and me. Frisk glared at me and stood up.

"Magic glue, actually. It wears off after a while." She explained, in a tone I didn't like. I stood up, and glared at her.

"I'm going to get you." I saw a bottle of syrup on the table and grabbed it right before she could. I grinned, and opened the bottle and proceeded to pour syrup on her head. Then I ran like I was being chased by a pissed off Undyne. I ended up going into the crevice where the monster candy was hidden. Frisk probably didn't see me. She walked right past me, which ended in me sneaking up on her and pouring more syrup on her. She yelped and I ran the other way… into Sans. I started blushing and struggled to pull away. Instead he teleported us to… his house?

"Sans? You ok?" I asked, still blushing uncontrollably in his arms.

"wrong place." He then teleported us to my house then left. Well then.

Asriel POV

I was leading Frisk through the Ruins, trying to find her sister, or Sans, for that matter. Frisk tripped and her knee got scraped. I knew that it'd most likely hurt her if she tried to walk, so I carried her- piggyback.

Her breathing eventually slowed, so I set her down and let her sleep, and sat down next to her, to start dozing myself. A few moments later, I heard her mumble, "Asriel, who do you like?" I didn't react, I thought she was dreaming. Instead, I decided to say the truth, "You." Then I heard her breathing hitch, and I realized; _she's been awake_ … "I like you too." She whispered into my ear, and I woke up from my sleepy state. I couldn't help it, but I had to hug her after that.

 **Ok… sooooooo Frisk x Asriel are my OTP… I should mention that… also I want to try to update everyday.**

 **But anyway, here's the next chapter hint: Hugs, A kiss, maybe a date, and an over-protective sister.**


	3. Chapter 3

**Sooo… I'm just going to point out that this is a little late… oops? Anyway, I'm sorry about the late chapter… anyway… where were we in the story?**

Frisk POV

I couldn't stop shaking. I was so nervous, I mean, I was about to tell my over-protective sister that Asriel had asked me to go on a date with him. No, I decided, I would just wait until after I take my shower.

After my shower I put on my blue sweater, and blue jeans, along with brown boots. **(A/N: basically her normal outfit, minus the stripes.)** I walked downstairs to see Katherine sketching. Now that no one else was in the house, I could ask her what it was without her getting all flustered. So I walked behind the couch and looked over her shoulder.

"Whatcha drawing? Seems interesting for you to be-." I stopped mid-sentence, and saw a picture of a goat skull floating above the ground aiming something at her. _This is one of her dreams…_ I thought; knowing well enough that she only draws things that stay on her mind for a long time.

"Shit, you ok? What was the dream this time?" she didn't answer me, not one peep. Her phone buzzed next to her and I noticed a stream of texts.

 _ **sans: hey. you ok? you looked dead when I dropped you off.**_

 _ **Undyne: Punk! What're you doing?! Papyrus says sans is freaking out!**_

 _ **Alphys: H-hey… are you ok? I heard Asriel asked Frisk out.**_

 _ **Muffet: hey, you ok? Your crush came by and asked if you stopped by. Ahuhuhuhu~**_

"Katherine? You… alright?" I looked at her, to see her asleep. I shook my head and wrote a note where I was and who I was with, and placed it on her phone. Then I left and went to Grillby's.

Katherine POV

I heard buzzing and tensed, thinking it was the skull again. I opened my eyes, to see my phone buzzing next to my leg. I let out a breath of relief and picked up my phone. The name 'Muffet' came across the screen. **(A/N: Muffet is Katherine's best friend, btw. More info at the end.)**

"Hello?" I answered, hoping this could last long enough to distract me from that dream.

"Ah, hello dearie~ how're you? ~" she asked, a simple conversation starter. Oh lord.

"Nightmares. You?" I flicked a piece of fuzz off the couch.

"Not really, buuuuut could we hang out tonight? ~ I'm bored and I saw Asriel walk past my parlor. And I don't snoop without my partner in crime. ~" I sighed and got up, to see a piece of paper that sported Frisk's hand writing on it. I skimmed the paper, and reread the third line. 'on a date with Asriel.'

"Oh, hell yeah we're fucking snooping. Asriel has a date tonight." I informed her, knowing she'd love the information.

"Ahuhuhuhu ~ that makes it more fun. ~ well, meet up with me at my parlor then. I'll be waiting. ~" she hung up and I closed my sketchbook, glaring at the picture it was stuck on. That Gaster Blaster burnt… ANYWAY! I walked out of the house and walked towards Snowdin.

As I walked into Snowdin, I realized it was probably too cold out for anyone to really travel for a long time. I mean, there was people out and about, but there wasn't as much people out as normal. I heard a commotion to my left, near Sans and Papyrus' house. I looked in that direction and saw Sans and Papyrus arguing as they left the house. I caught a little bit of their conversation (it's not creepy if Papyrus is yelling).

"SANS! WHY DO YOU KEEP CHECKING YOUR PHONE?! IF SHE HASN'T ANSWERED, THEN SHE'S PROBABLY TRYING TO AVOID YOUR PUNS!" Sans just shook his skull, and shut off his phone to appease the taller skeleton.

" _tibia_ honest pap, i think she might just be asleep." Papyrus just scoffed. I decided to leave them to their bickering.

I got to Muffet's parlor in an hour, with the convenience of the river man or woman. Still can't tell. Anyway when I got there she handed me a black dress and insisted I wore it and not pull the bullshit I normally do. Which is where I say it doesn't fit and that I refuse to wear it… ANYWAY, after I put on the dress I just stared at the mirror in shock. It went down to my knees, and had a red sash that pulled at my waist and made my chest stick out a bit too much for my liking. Muffet handed me blue fingerless gloves that she insisted I wear. For some reason she got a call in the middle of her nagging and I heard her say "yes, she is wearing the outfit. ~" or something like that. I pulled on a black beanie **(A/N: at the end I'll explain Katherine's *slight* obsession with wearing black)** and waited for Muffet to finally be ready to go.

Thirty minutes later and we were sitting in the restaurant (at MTT resort) and I spotted Frisk walk in with Asriel and- OH MY FUCKING GOD ASRIEL BETTER PRAY FOR HIS FUCKING SAFETY! He was holding her hand. Muffet probably noticed me staring in their direction and it took her all her strength to not squeal and give us away. I took out my phone and took a picture and sent it to Muffet. Frisk and Asriel sat a few tables away from us and I saw them chat for a while.

Frisk POV

OH MY GOD OH MY GOD OH MY GOD OH MY GOD OH MY GOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOD I AM SO NERVOUS RIGHT NOW!

 _ **Ding!**_

I looked down at my phone and noticed I just got a text.

 _ **Ink hands: Hey. How's the date? I woke up and just read your note. AND WHY ASRIEL?! I'M GOING TO WRING YOUR NECK AND HIS IF YOU ARE MISSING ONE POINT OF HP, GOT IT?!**_

I stared plainly at the phone.

"Heeeey, so my sister just sent this to me…" I showed him the text and he paled as he finished.

"Um, she isn't that serious about that, right?" he asked jokingly. "Oh, she's serious." He paled more. "The only way you could get hurt is two ways…" he was blushing a bit and sheepishly rubbing the back of his neck.

=-=(Time skip to after date)=-=

Katherine POV

They just left… and Muffet is saying we follow. URGH. So we did.

"So, how's it going between you and Sans? He stopped by asking me if you had come by, but you hadn't. And he looked really disappointed too. You two should talk. ~" she grinned at me and I just sighed.

"I think your shipping imagination is going on overdrive. Even if it started when we saw my sister and Asriel on a date." She just laughed and we went our separate ways.

I got home pretty late, maybe twelve o' clock. I plopped down on my pillow in my room and entered the realm of nightmares.

Frisk POV

Asriel walked me home, and we had casual talk along the way. When we got to the door though, Asriel quickly kissed me on the lips and hugged me. And had the cutest blush on his face ever. I pecked him on the cheek and rushed inside. Man, Katherine is going to kill me.

(NEXT MORNING!)

Katherine POV

 _ **The Great Papyrus: OLDER HUMAN! SANS KEEPS CHECKING HIS PHONE TO SEE IF YOU OR FRISK ARE ANSWERING YOUR PHONES. SO I, THE GREAT PAPYRUS HAVE INVITED YOU TWO TO MY HOME, SO WE COULD ALL PARTAKE IN SPAGHETTI! NYEH HEH HEH!**_

"FRISK! WAKE UUUUUUP! WE'RE GOING TO SNOWDIN!" I waited, then she came downstairs. "Whyyyyyyyyy…I was asleep!" I showed her the text. She immediately brightened up.

"Well, go get dressed."

 **I'm so sorry that this is late… anyways heres some info that I promised.**

 **Katherine is a goth and she wears black all the time… so pretty much everything she wears is black. As for Muffet being her best friend… my friend and I see Muffet as a goth and I think next chapter I'll include some flashbacks on how the girl's journey was in the Underground. ANYWAY I apologize that this came out WAAAY later than planned. And next chapter… well lets say it will be quite… shocking?**

 **Anyway… I'm wondering if there should be lemon in this…**


	4. Chapter 4

**So. Heres the chapter.**

Frisk POV

Thirty minutes later we're walking to Snowdin, and up ahead I saw the monster kid talking to Papyrus. (still have no clue what that kid's name is.) I smiled and waved.

"Yo! Papyrus, look! Frisk and Katherine are here! Well, I gotta go! Bye!" He ran off, yet still tripped onto the snow; but he got up with a smile and continued running.

"HUMANS! I, THE GREAT PAPYRUS, HAVE COME TO WALK YOU TWO TO MY HOME! UNDYNE AND DR. ALPHYS HAVE JOINED US, ALONG WITH METTATON, ASRIEL, ASGORE, AND TORIEL! SANS IS MOST LIKELY TORTURING THEM WITH PUNS RIGHT NOW, SO IT IS BEST IF WE HURRY." Papyrus grinned and started walking into Snowdin. I froze when I heard Asriel's name and flushed. I saw Katherine walk past me and smirk.

We finally got to the house and man, it was chaos…. sorta. Asriel was blushing and his parents talking to him about something, Sans and Mettaton were shouting at one another, and Undyne was shouting on how she'll arrest everyone if they don't shut up (ahem, sans and Mettaton…) while Alphys was reminding her- or attempting to; that Undyne was no longer a royal guard. Katherine coughed, loud enough to get Alphys' attention. Said person walked over, and greeted us.

"H-hey. H-how's it going? It'll be chaos really, really soon…" I looked to see Papyrus setting the table, and about to announce that dinner's ready.

"DINNER IS SERVED!" the chaos ended then and everyone sat and calmly ate.

Afterwards, Undyne had the worst/best idea ever. Truth or Dare.

Katherine POV

I hate Undyne. I officially do. I really do.

We all ended up sitting in a circle in the living room, me being against the couch, Frisk on my left and Sans on my right. Undyne stared right at Sans, and laughed.

"Sans, truth or dare?" She smirked, clearly proud of herself for choosing Sans. (don't know why though…)

"truth. i'm too lazy to do a dare right now." Sans grinned and She glared at him.

"Sans, if you could kiss anyone in this room, who would it be?" Undyne sneered, and Sans flushed blue.

"i cant believe i'm admitting this…" He picked up a ketchup bottle. "but, i'd kiss this ketchup bottle." I burst out laughing at Undyne's reaction. Papyrus was facepalming, and Toriel was laughing along with me. Mettaton just stared at him, and scoffed. Asriel and Frisk were just sitting next to each other, holding hands, WAIT WHAT?!

"ok. my turn, right? frisk, truth or dare?" Sans just waited for her response.

"Dare." Frisk said that a little too confidently, and Sans grinned.

"i dare you to sit on asriel's lap the rest of the game." OH HELL NO! Frisk turned beet red as she sat on Asriel's lap. Asriel was worse, his face and neck were bright red.

"Toriel, truth or dare?" Frisk had a smug look on her face, and one Toriel could guess was an evil one.

"Dare." I heard Sans hold back a snicker.

"I dare you to kiss Asgore." I couldn't help it. I started laughing and caused Sans to laugh along. Toriel just blushed and quickly kissed the overjoyed goat man. I heard my name be called over my laughter. Shit.

"Katherine, truth or dare?" I felt a little risky… maybe saying dare wouldn't hurt…

"Dare." She looked pretty bold, it seriously couldn't be that bad… could it?

"I dare you to… draw on the person to your right, in whatever condiment they want you to… and it has to be on the head, and chest," Toriel paused, most likely waiting on my answer. "But you have to lick it off them after you're done." I was literally about to say "Ok." but now I'm thinking I jinxed this bullshit. I looked to my right and saw Sans already holding ketchup. That asshole.

"Fiiiiiiine." I held out the word, and Sans took his jacket and shirt off so it wouldn't get messy. **(A/N: Oooooooooooooooooooooooooh! Such sin in one chapter!)** I took the ketchup and started doodling on his forehead. A bit of ketchup nearly dripped in his eye, and I was not about to lick there. I swiped the ketchup above the eye, and he tensed for a sec. After I used nearly half the bottle, I moved to his ribs, and I knew I was blushing. I finished a few minutes later and I noticed nearly everyone had their phones out. Assholes.

I started licking on his forehead and I cringed. The ketchup had gotten warm, and the ketchup that was on Sans's nose had gotten on my neck. I heard giggles erupt all around me, and Sans's breathing had gotten a bit funky. I worked my way down, making sure I avoided his mouth as best as I could. I noticed that he had a blue tint on his cheeks. Holy fucking shit why is he blushing?!

I got to his chest and looked at Toriel for mercy. Nope. Stone cold eyes. God damn. I started to lick the ketchup, and gagged. Nope. Not eating ketchup anymore for the rest of my life. I quickly licked the rest of the damned substance and sat up. As if timed, I got a video sent to me of that entire thing happening.

"Assholes. Papyrus, truth or dare?" I rubbed the ketchup around my lips off.

"TRUTH! I AM SORRY, OLDER HUMAN BUT AFTER WITNESSING THAT, I REALLY DON'T THINK I SHOULD SAY 'DARE'." I nodded at his reasoning.

"That's ok. So, Papyrus, who would you date in this room if you had the"-

"METTATON!" I laughed and Sans nearly attacked the poor, shocked robot. I pulled at his arm, and he retreated.

"SANS! PUT A SHIRT ON!" "ok bro." "NOW!" "ok." "YOU ARE MAKING EVERYONE UNCOMFORTABLE." "oops. _tibia_ honest, i think it's just you, bro." "NYYYYYYGGGGGGGGGGGAHHHHHHHHHHHHHHHH" "heh. you're smiling bro." "I AM AND I HATE IT." Sans put his shirt on, thankfully.

"Asgore and I are leaving now, Asriel. Don't stay up late, alright?" Asriel nodded and his parents left.

"Hey, punks! We're going now! We have crap to do! Bye!" Undyne carried Alphys and Mettaton out of the house, Papyrus following.

"She says, while taking most of everyone here with her." I heard Asriel mumble. "Yep" I sarcastically answered, and climbed onto the couch. I remembered when Frisk came here for her date with Papyrus, and I had just hung out on the couch. Man, I miss that. I felt sleep pulling me into dreamland. And soon, I was asleep.

I was in the last corridor, along with Frisk, and I could see Sans down the hall. I looked at my arms, which were covered in dust. I looked down at Frisk, who was wielding a knife, as was I. We both had heart lockets on, hers red, and mine black. Frisk's sleeves appeared to be stained with the same dust I had. I unwillingly took a step forward, towards Sans's location, as did Frisk. We both calmly walked forward and Sans grinned.

"back for more, huh? well, i'm not going easy on you this time." Frisk and I were straight away put into a fight after that. I felt a morbid grin takeover my features. I knew Frisk was doing the same. We both attacked him, but he just dodged. _I don't want this! I have to let him kill me! I can't do this!_ I should've known better. My body did its own thing, dodging everything he attacked us with. We got to a point where I could control my body, and Sans was offering us mercy. I spared him, and dropped my knife and walked towards him. Pain shot up my body, and I saw why. It was a trick. He had shot bones through my body. I was dying.

"geeeeeeeeeeeeeeet duuuuuuuuuuuuuuuunkked oooooooooooooon!" I heard him yell, which was unusual of him.

I woke up, panting for breath. I was still on the couch… and Sans was next to me.

"O-oh hey… what happened?" I asked, because, obviously, who wouldn't ask that if they just fell asleep on their friend's couch.

"you just woke up. thats what happened." Never mind. I got up, the dream still fresh in my mind.

"Where's Frisk?" I mumbled, looking around, and not seeing my sister.

"she went home a while ago. she said that she didn't wanna wake you. so she didn't." I nodded, and pulled on my hoodie.

"hey. i… i heard you mumbling some stuff in your dream… and uh, just bend down to my height real quick." I did and looked at him, clearly puzzled. I felt a spark on my lips, and realized that he's kissing me… I kissed him back, and pulled away, blushing.

"I-I need t-to get home…" I stuttered, and I was feeling suddenly shy around him.

"i'll walk you home." So we walked together.

 **So. That happened. And I replaced the flashbacks with the dream. And next chapter, I'll show what happened after Katherine fell asleep. I also feel pretty good about this chapter. So… yeah.**


	5. Chapter 5

**And welcome back folks! Honestly, I'm feeling pretty good about this so far, and, I'm wondering, what should be in the next chapter?**

 **Double Date…**

 **Asriel X Frisk**

 **OC X Sans**

 **PAPYTON.**

 **Review your answer please….. the most requested shall be chosen.**

Frisk POV

I looked at my sister, to see her dozing off on the couch. She looked calm, to say the least. She fell asleep, soon after Asriel and I were about to leave.

"Tell her I didn't want to wake her up." I glared at Sans, and he nodded and looked at her. "I know you have feelings for her, too. And I'm just saying this now, if you so much as touch her, I will hunt you down."

"um, ok?" he looked confused, but I could see sweat forming on his head. Asriel and I walked out of the house, and I felt proud that I had made the skeleton a bit nervous. Asriel's hand found mine and he held my hand and we walked to my house.

Sans POV

I felt incredibly nervous, in my house alone with my crush.

"I don't want this! i… I have to let him kill me! I can't kill sans…" I heard Katherine mumble in her sleep. She squirmed a little while later and I saw bruises forming on her arms then disappearing a little while after. The hell? She then woke up, panting, and looking around. When she saw me staring at her, she started speaking.

"O-oh hey… what happened?" she asked, and had the cutest expression on her face. I wanted to pull out my phone and capture that, but… I couldn't.

"you just woke up. thats what happened." She made an annoyed expression, and got up. so I did too. I barely heard her next question.

"Where's Frisk?" she was looking around for her.

"she went home a while ago. she said that she didn't wanna wake you. so she didn't." that was my response. I remembered what Katherine had mumbled. I stared at her, and she was pulling on her hoodie. _Damn it. Now or never._

"hey. i… i heard you mumbling some stuff in your dream… and uh, just bend down to my height real quick." She turned and came down to my height. I quickly went forward and kissed her on the lips. I felt shock course through me when she kissed me back. I was about to kiss her again when she pulled away. She looked adorable with that red blush.

"I-I need t-to get home…" she stuttered, and looked really shy all of a sudden. So we started walking towards her place. Then I remembered Frisk's warning. DAMN IT!

I looked up at Katherine, and felt a little awkward just walking.

"so… about me kissing you earlier… i… i always wanted to do that kind of thing with you… kissing, i mean." She blushed more, and I decided she was adorable like that.

"I… I've sorta felt like that since we started hanging out. Muffet keeps making fun of me cause of it." Her hair fell in her face and she looked so cute.

"i started liking you when I saw that shirt you wore when we first met." She looked at me, then remembered.

"The skull tank top? I froze in that, by the way. Why'd you like that…?" I liked it for two reasons. The skull, and… well I'd rather not say the second reason.

"the skull."

"… fuck you." I smirked.

"c'mere." She looked at me, and I struggled to show I wanted her to come down to my height again. But she figured it out anyway. When she got close to my height, I pulled her down to my lips. I heard her yelp, and then she kissed me back. I licked the bottom of her lip, but I tasted something… off. I realized what it was and started laughing.

I pulled away, and I couldn't stop laughing. She looked so confused.

"y-your… l-lips… taste… like ketchup…" I couldn't stop laughing, not at this point. I noticed she was blushing. Again.

"Not my fault Toriel dared me to do that!" she exclaimed, loud enough for me to hear over my laughter.

"yeah. but it is your fault that you said 'dare'." She blushed more. "but… i like the taste of ketchup." i walked over to her and trailed kisses from her mouth to her neck. I started sucking on various places on her neck, and I could see hickeys forming. I was thankful that it was late and no one could see us.

"SANS! GET AWAY FROM MY SISTER!" I jumped away from Katherine and she looked slightly confused. When she realized what happened she turned around and waved at a very pissed off Frisk.

"fuck."

"Yep." Frisk then came over and glared at me.

"Sans."

"yes?"

"I warned you, didn't I?"

"you'll have to be more specific." Katherine laughed after that.

"Sans." Frisk warned me, a glare was settling once again.

"yes?"

"Don't joke. What did I warn you about?"

"you'll seriously have to be more specific. i am quite a _bonehead_."

"Before Asriel and I left your place. What did I say?"

" _Tell her I didn't want to wake her up_."

"Not that."

"well i don't remember anything else after that. oops."

"MMPH!" Katherine had placed a hand over Frisk's mouth.

"Okay…. Well, I'll see you later, ok Sans?" I nodded and I watched them walk away. _Fucking hell._

Frisk POV (When Sans and Katherine had their shippy moments.)

"I'm bored." I heard Asriel say in the living room.

"Why? Let's just watch the video of Katherine licking the ketchup off Sans."

"We've already watched that."

"We haven't seen the one Undyne recorded."

"…" he looked hesitant. "Let's watch it."

I pulled out my phone and we got a full view of what happened. I snickered when Katherine got to Sans's chest. She looked so flustered at that point. And sick of ketchup.

 **(A/N: I hate too much ketchup… I personally love mustard, and according to my friend, Katherine should too.)**

I felt Asriel laying his head on my shoulder, and his breathing slowed. I turned my head and I kissed the top of his head. He snapped his head up and blushed.

"Not my fault Toriel dared me to do that!" I heard a voice call down the road from the house.

"What the hell…?" I got up and started walking to the voice, to see Sans kissing my sisters neck. OH HELL NO!

"SANS! GET AWAY FROM MY SISTER!" I yelled, and the bastard jumped away from her. Katherine looked pissed at me, but I did not fucking care. I did not want my older sister making out in the snow.

(time skip to when Katherine and frisk got home)

Frisk POV

"Frisk. Why the hell did you do that?" Katherine complained when we got home.

"Because. He. Was. Kissing. You." I was about to insult the skeleton when Asriel interjected.

"Um, what happened…?" I didn't answer, because I was starting to notice the blue marks on Katherine's neck.

"Frisk yelled at Sans for kissing me." Kathrine explained, and completely oblivious to the fact that she had blue hickeys on her neck.

"Katherine." Asriel said softly.

"What?"

"Look at your neck…" Asriel told her before I could. She made a face and walked to the bathroom. I saw her hoodie fly out of the room, showing she literally threw it off.

"What the fuck? How the hell did that happen?" I walked in to see her examining the hickeys. Asriel walked in and immediately walked out. She was in just a tank top. I walked up to her and took a picture of the hickeys and sent them to Sans.

 _ **sans: the hell is that?**_

 _ **Me: a hickey from you. that's on Katherine right now.**_

 _ **sans: oh. i thought it was something bad.**_

 _ **Me: SANS I WILL FUCKING KILL YOU.**_

 _ **sans: ouch. why?**_

 _ **Me: I want no proof of you on her body. ITS BRIGHT FUCKING BLUE TOO!**_

I turned off my phone and ignored him.

"We need to get rid of that." Katherine glared at me.

"Hell no. its staying."

"Katherine." I warned, trying to win this argument.

"Frisk." She used the same tone. Damn it.

"It needs to be covered up."- "Its gonna be shown. Deal with it bitch." She remarked, a look settling on her face. "And is Asriel sleeping over?"

"If he wants. HEY ASRIEL?"

"Yeah?" he started climbing the stairs, and got to us.

"You sleeping over?"

"Sure, why not?" I felt excited at that.

"Good. I'll ask Sans if he can sleepover too then." Katherine grinned and I suddenly knew why she asked if Asriel was sleeping over. I saw Katherine quickly type something and five minutes later a knock was on our door. Damn.

"I'm getting it." Katherine was about to answer the door, where Sans was located, in a tank top.

"No. I will." And Katherine was already answering the door. GOD DAMN IT!

When she answered Sans was already about to pull her down to his height.

"HEY!" bam. Get away from my sister.

Sans glared at me, and hugged Katherine at her side.

 **So I feel like I should explain Sans and Katherine's height differences. Katherine is pretty tall, and Sans is up to her… *Ahem* chest. Frisk is nearly as tall as Katherine, but Asriel is taller than both Katherine and Frisk. Anyway. TWO CHAPTERS IN ONE DAY! WHOO HOO! :D I'm proud that I was able to pull it off. Now please remember to say:**

 **A) Double Date…**

 **B) Asriel X Frisk**

 **C) OC X Sans**

 **D) PAPYTON.**

 **And please. There have been 439 views on this… why do I feel like that isn't possible…?**

 **And I'm going to ask again….. should I incorporate lemon into this? I've been thinking about it, but I don't know.**


	6. Chapter 6

**So. Asriel and Frisk seemed to top the list with four votes. And I wanted to thank everyone who reviewed. It makes me happy to see people are enjoying my story. And now, what you've all been waiting for! Chapter six!**

Frisk POV

I stared at the sparkly flyer labeled 'The Monster Mash!' I read it over and it was a date thing… OH SHIT!  
I walked inside, where I saw Katherine watching TV, where Mettaton was announcing the dance. I glanced at the flyer and stuck it in her face.

"Get that away from me! It smells like someone barfed glitter all over it." She remarked, shoving the flyer out of her face.

"Just read it. You have to have a date for the dance…" once the words left my mouth she darted to her room to hide her blush. The picture of her hickeys somehow had gotten from my phone onto the internet. This is not my doing, for sure. Sans had been constantly trying to find out who posted it, and cannot track them. It was someone from the Underground, and Katherine had mumbled stuff on it being a damn stalker.

Ever since the picture was posted, I was the only person she spoke to, or even allowed herself to be around. The hickeys had gone away, but she won't reply to Sans or Muffet.

I quickly dialed Mettaton's number, hoping that he'd at least answer.

"Frisk, darling, is this you? Calling about 'it'?" Mettaton had answered, YES! I sighed, stupidly reminding myself that the robot always memorized a number, voice, eye color, body shape, personality, hair style, etc. That was just his 'thing', as Katherine would put it.

"Yea, it's me, Mettaton. I was wondering, did you find out more on that human that fell recently?" Oh yea, a new human. It was a male, as far as I knew.

"Oh, why yes I did. His name is Logan, and he is twenty-one years old, like Katherine, slight bit of a geeky nerd, but could look like a hunk if dressed properly. He has a ton of freckles, and light blue eyes. A bit close to Sans' height, maybe even shorter. He has slightly wavy light brown hair, sort of like your sisters. Minus the dye. He has a fatal allergy to bees, and peanuts. Need any more info?" I was speechless, honestly due to how much info Mettaton just fed me. And the fact that he had MORE was astonishing.

"I-I think I'm good Mettaton. Thanks. See you at the party. Bye." "Bye darling." I hung up, and sent a quick text to Asriel asking him to come over. He responded with "Be there soon." Now to tell Katherine that Asriel is coming over for dinner.

-*-time skip(dinner)-*-

So… Asriel brought Logan with him. And now Logan may like Katherine, because apparently he was specifically warned that I was Asriel's girlfriend.

So, right now I was texting Sans under the table telling him what was happening. And he was so pissed, I'm pretty sure I could hear his scary, yet catchy song playing down the street. It always seemed to be the song that played whenever someone was going to have a **bad time**.

 _ **Sans:**_ _whats the prick doin right now?_

 _ **Frisk:**_ _Oh, you know, the occasional glance at her, or her arm, neck, stomach, aaaaand I just caught him staring at her chest._

 _ **Sans:**_ _THAT'S IT IM COMING OVER THERE!_

 _ **Frisk:**_ _Don't get pissed, I'm kidding. Maybe._

 _ **Sans:**_ _-3- does katherine notice?_

 _ **Frisk:**_ _dunno. Maybe. But I'm not going to ask if he's still here. I got to go, sorry._

I shut off my phone afterwards.'

"H-hey, Katherine? I've heard about this 'Monster Mash' thing that's happening soon, could you possibly go as my date…?" I heard Logan ask my sister, and I was about to stand up and start calling Sans to get down here, ASAP. Everyone watched Katherine, waiting for her answer.

"I… I guess…?" I heard her answer, and prayed that she'd get out of this potential love triangle soon.

-*-(time skip)-*-

Asriel and I are walking in the forest, just talking and holding hands. I felt… odd, for certain. I honestly felt like pushing Asriel against a tree and… I'll let your imagination go off there. Suddenly, I felt determination swell up inside me, right as we passed a tough looking tree. Damn it determination. So I, now filled with determination, pushed Asriel into the tree and kissed him. Nothing special, but it's something that randomly occurred. Like drawing a number out of a hat.

_-_(warning, this part has lemon in it.)_-_

He kissed me back, and spun us around so that I was against the tree. I noted that right when I kissed him back, his hands dropped to my waist and swarmed my covered torso. He started sucking and nibbling my lip, somewhat asking for entrance. I stifled a light moan, and opened up. I started to wonder how this worked, because of him having a snout and all, but these thoughts were whooshed away when he started to suck on my neck. I moaned, not caring anymore. He took this as a good sign, and trailed down to my collarbone, making me moan along the way. Meanwhile, his hands had snuck under my sweater, and were busy unclasping my bra. Once it had come undone, he threw it onto the ground, my shirt going with it. I started to tug at his shirt, and moaned when he sucked on my right breast. He pulled his shirt off, and my hands immediately grabbed him by the shoulders. He started to slip a hand into my pants and all I could think about was how _warm_ it was down there. I felt his fingers graze along my skin, sending electric tingles where he touched. I felt a finger slide in, and moaned in pleasure. He maintained a pace, and I realized that he was feeling aroused while fingering me. So I casually slid my hand into his pants, where a pretty big bulge was already formed. I grabbed him firmly, and worked my way up and down, taking his grunts and pants as determination fuel.

Eventually, our pants and underwear was shed and we kept teasing each other. He slid his two fingers out, and licked off the liquid that rested on them.

" You make quite the mess, Frisk." I hummed in response, and stopped messing with his member.

"You want to fuck me so hard that I'll forget my name?" I asked, eyeing his growing member as the words left my mouth.

"You sure are tempting me… maybe some persuasion could help you get what you wish for." I thought for a while, and got an idea.

"Alright. Sit down, and enjoy my _persuasion_." After he sat down, I sat in front of him, legs spread apart. I slowly slid one hand to my aching crotch, and the other to my chest. I slid two fingers in, and caressed my breast. I moaned Asriel's name, fingering myself, and bucking my hips to get him over here, and have him take me. It took five minutes before I was pinned by Asriel, and him holding both of my hands above my head, while he started thrusting into my crotch, grunting and panting, while I moaned his name.

We both ended at the same time, and in a hazy blur, got dressed, and walked home.

_-_(lemon end)_-_

At home, was quite the scene. Sans was at the house, sitting on the couch while staring down Logan. Katherine was nowhere to be seen. Shit, she's hiding again.

"Who did it?" I asked, making Asriel and my presence known.

"he did it!/He did it!" Sans and Logan pointed at each other, all the while in unison. I sighed and walked to Katherine's room, ignoring the signs saying 'do not enter' or 'Satanism at work'.

In her room she swung on her hammock, which was in the corner of her room. I could see her mass of hair puffing out of her blanket.

"Who said it? And why are you in here, when Sans is out there?" all I got in response was a middle finger.

"Sans showed up, I don't why, but he did. And when he saw Logan and I talking, he suddenly got"- she sat up, face pale.

"So, I may have told him Logan asked you to the dance…" she groaned, and repeatedly hit her head on the wall.

 _Knock. Knock._

"Who's there?" Katherine was looking at the entrance of her room as she answered, and she knew fully well who it was.

"a door." She knew what was coming. "Ohhh hell no." she got out of her hammock and walked to the door where Sans was grinning. "No Sans, I am not letting you finish that one."

"aw, c'mon katherine, it was gonna be _humerus_." She rolled her eyes, though it was pretty obvious she thought it was funny.

"Yea, stop. She obviously doesn't care for your puns. Plus she did say yes to go to the dance with **me!** " Logan spoke up, and wrapping his arm around Katherine, who froze, and stared at Sans, whom was looking at her with remorse.

"is this about the hickeys?" katherine shook her head no, clearly not trusting herself with words. "then what the fuck is this about? i know we aren't dating but i still like you. whats going on? you've been ignoring everyone! And now youre letting this prick hold you like youre his?!" she looked away from Sans, and pulled away from Logan.

"I'm leaving and not coming back." She then bolted out of the house, and ran out into the underground.

…

…

…

 **So! That's it for this chapter. Sorry it took FOREVER, but complications came up with my fucking computer, and I really lacked ideas for this story. So if you ever have ideas, just PM me. So yea, see you next time!**


	7. Black & Blue

**So. How is everyone after last chapter? Trust me, I was kinda hoping to get this up a LOOOOOOOOOONG time ago. never did tho.**

 **Also, I have a plate of cookies here from Diamondgirl, and they're kind of cold and have cobwebs on them… hehe…**

 **Anyways, someone sent me a PM requesting Sans/OC drama since I pulled that bullshit in the last chapter.**

Sans POV.

I watched as she ran out of her house, barefoot and wearing only a tank top and sweatpants. She didn't bother with closing the door- the blizzard outside did that for her.

"KATHERINE!" I couldn't stop myself, and ran out the door after her. I couldn't see anything, except her footprints which led deeper into the forest. I then remembered the edge- the place where monsters will give up- and that she wouldn't see it. I couldn't stop images of her falling and hurting herself.I had a flashback of when I saw her and Frisk in their first fight with Papyrus.

 _He couldn't see their souls yet, but he definitely had to know if they were dangerous. He always had been able to see into souls and see the owners personality and such._

 _He watched as Katherine and Frisk's souls popped out, and he analyzed their colors. Frisks soul was a ruby red, and she had a genuine goal to be a pacifist. He moved his gaze to Katherine's soul and gasped._

I shook off the memory, and noticed a lump in the snow up ahead, right away I knew who it was. Katherine.

"KATHERINE!" I started running towards her, and I saw immediately that she was shaking and mumbling to herself. Gently shaking her, I whispered her name in hopes to get her to snap out of it.

Katherine POV.

I could hear Sans in the distance, but all I could hear was that static and whispers in my ears. I started shaking- whoever was shaking me I did not like it. I wanted this all to be a dream. I want this to be a dream. I need this to be a dream. I REALLY NEED THIS TO BE A DREAM!

Sans POV.

I got her up, and moved the hair out of her face after she snapped out of it and stopped crying.

"hey, you ok? i don't really see you get like that, what happened?" I asked, putting my jacket on her. I waited for her to start signing, because whenever she or Frisk are nervous, scared, or upset, they'll start signing.

' **I don't know.'** Signing really slowly so I could decipher it. Nodding, I picked her up princess style and started walking back to her house. As we entered, Frisk and Asriel were waiting for us, and apparently that shit bag Logan left once Katherine bolted.

"She ok? did you do anything to her? She looks traumatized!"

' **Frisk, I'm ok! seriously! I …. Happened…..I'm fine.'** I lost some parts of that but that's mainly because she was signing really fast. "SANS SHES SIGNING WHAT DID YOU DO?!" Asriel was attempting to hold Frisk away from me, helping me not turn to dust.

"Frisk, lets play Truth or Dare to get Katherine happy! That'll calm both of you down, won't it?" Katherine and Frisk both nodded and unison and Katherine hopped down from my arms and handed me my jacket. She sat next to me, while Frisk and Asriel sat across from us.

"Asriel, since you suggested you start." Ok, katherine was speaking now.

"Sans, truth or dare." Not taking the risk. "truth." he contemplated his options, then looked me in the eye sockets.

"Why haven't you asked Katherine out yet?" the poor girl instantly lit up red. Right. we still haven't told them… I asked her out in the woods… and she's going to cancel being Logan's date for the dance.

"w-we are dating…?" If Katherine was a tomato, I was a blueberry. He turned to Frisk "Called it. I decide what we're doing next time." Frisk rolled her eyes.

"katherine. truth or dare?" "Dare" "i dare you to let me see your soul." She complied and pulled out her soul. I stared at it, the darkness of it giving it its own personality. She cupped the black soul, and brought it near my skull so I could look at it. She knew how much I loved seeing her soul, like it's the biggest thing ever. Alphys has researched it, and couldn't find anything. Not even a tiny sample. Yes. Katherine has a black soul. It makes her more prone to be traumatized and succumbed to evil and darkness. I pulled her hands closer to me, and kissed the soul. I saw her noticeably shiver, and her blush only deepened.

"Get a room you two." Frisk sarcastically said across from us. Katherine shoved her soul back into its place and looked at Frisk.

"Frisk, truth or dare?" "Truth" "Have you and Asriel fucked?" I burst out laughing, and the two in question blushed more than katherine. Frisk slowly nodded. "Use protection until you're married. I want nieces and nephews." I started laughing even more. I loved her.

"Katherine! Truth or Dare?" Frisk had something planned…. "Dare!" Frisk grinned.

"I dare you to go into your room with Sans and give him an extra bone, if you know what I mean." Oh my god… I don't know if Frisk did me a favor or not.

And a few minutes later we're walking up to Katherine's room, and she looks embarrassed as hell. Right when I close the door and take a few steps, I'm pinned to a wall. Fuck.

"S-sans… I-I just need y-you to sit on the bed, and I'll try to get it over with as fast as I can…" she moved away, and grabbed a cloth, to wait for me to sit down. I sat down, and she tied the cloth around my eye sockets.

 **(A/N: so I should've mentioned in this chapter, there is going to be slight lemon… ok a lot of lemon. And it starts here.)**

I felt Katherine move my legs to a straight position, and then straddle me. I noted her hands going to the back of my skull and holding it there. She then started grinding on me, and fake moaning where my ear should be. I froze up, and a blush creeped on my skull. I noticed one of her hands crawling down my shirt and tugging at my jacket, which I discarded right away. I didn't realize that she had started undressing too, and was only in her underwear. She took the blindfold off me, and tugged at my shirt with one hand while the other was on my cheekbone. I pulled off the shirt, then felt her kiss me. I pulled her closer by wrapping my arms around her waist. I felt something squish against my ribcage, and broke the kiss to see something I've desired to hold for ten years. Her chest. I tugged at the underwire of the bra, and she skillfully unlatched the bra for me to throw. I kissed and sucked at her neck, which soon after I found the sweet spot, and made her unleash an abundance of moans. I moved down and licked a nipple, and pinching the other one. She arched her back and moaned. "S-sa-ah…" she started fingering the hem of my shorts. Getting the message, I took those off, only to throw them to the ground. I pulled at her panties, she also got the message. Once naked, she stared at my crotch like it had a head.

"Where's your… dick?" oh. that. "magic. wanna see?" she watched as I conjured up a blue penis. She grinned sadistically and bent down to mumble something on the tip. "I can't have all the pleasure you know. I have to share." And without warning, dipped her head down taking all of me in. I moaned, and bucked my hips and I could feel her groan on it. "o-oh f-fu-fuck k-katherine… trying t-to m-make me cum r-right a-away huh?" she nodded and I gently moved her head up. "no way. not until i'm inside you." she whimpered, but laid down on the bed and was prepared to let me in. I knew she was still a virgin, and was thankful that she had black sheets. I heard that there was a lot of blood involved when taking a humans virginity, so I had tibia gentle. I hesitated before I went in, staring at her reluctantly.

"It's ok, Sans. You're the only one I want to do this with. So go ahead." I kissed her to muffle her cry of pain as I went in. I felt something break and she started crying at the pain. I stopped and wiped her tears away.

"it's ok, it's ok. i'll let you adjust, and let me know when you're ready." A second later she bucked her hips, wanting to continue. I started moving my hips, and she started panting and moaning. I decided to pull her up and hold her. She wrapped her legs around my waist, and pretty soon we had a rhythm going. I let out a throaty groan when she started licking my neck. I decided to make it even and bite her collarbone. She let out a loud moan as I did that, arching her back while moving her head to give me more access.

"S-sans… I-I'm about t-to c-cum.." "same." Pretty soon we both ended, and her falling off of me and onto her pillows. I put a blanket over her and got dressed, then laid down next to her.

Frisk was not happy in the morning.

 **CHAPTER END! BAM! Ok, so I admit, that might've been REALLY descriptive, and I really need to say something. Katherine and Sans did not randomly have sex, this was planned by Frisk, hoping to get a move on with her sisters relationship. And I am planning on putting kids into this story. This story wont end.**


End file.
